text: An article investigating the structural basis of interactions between clinically relevant antibiotics and the 50S ribosome appeared in Nature in October 2001. High-resolution X-ray crystallography established that these antibiotics associate only with the 23S rRNA of a ribosomal subunit, and no interactions are formed with a subunit's protein portion. The article stresses that the results show "the importance of putative Mg ions for the binding of some drugs".